The present invention relates to an optical collimator-use lens component, an optical collimator, a method of assembling the optical collimator-use lens component, and a method of assembling the optical collimator, with which an optical fiber for optical communications and a lens are optically coupled to each other and emission light from the optical fiber is converted into parallel light or parallel light is condensed by the lens and is brought into incident on the optical fiber.
When a high-speed and large-capacity optical fiber communications system is structured, many optical devices are used. The optical devices include: an optical device that extracts an optical signal having an arbitrary wavelength from among multiple optical signals whose wavelengths have been multiplexed; and an optical device that uses an optical crystal for matching phases of optical signals, and many optical collimators are used therein which each convert a widening optical signal emitted from an optical fiber into parallel light.
With a conventional optical collimator production method, as shown in FIG. 14, a capillary tube 3 with an optical fiber 2 is first fixed to a thin tube 1, helium-neon laser light L generated by a visible range light source is caused to be emitted from the optical fiber 2, a lens 5 held on a precision stage 4 is aligned so as to have an optically appropriate positional relation while the collimated state of the laser light L is observed using a projection stage 6, and then the lens 5 is fastened to the thin tube 1 using an epoxy-based adhesive 7.
With the conventional assembling method described above, at the time of assembling, the laser light L is actually caused to be emitted from the optical fiber 2, so that it is required to connect the light source and the optical fiber 2 with high precision at a several μm level. The requirement leads to a problem in that preparation for production of the optical collimator, such as work concerning the alignment and processing of the optical fiber 2, takes much time and labor and workability is extremely low.
Also, with the conventional assembling method, the actual holding margin of the lens 5 is less than several mm and the alignment of the optical position requires high precision at several μm or several tenths of μm level, so that there is a problem in that the workability is further lowered.
Further, at the time of the optical position alignment, a gap exists between the lens 5 and the thin tube 1, so that there occurs a problem in that when the adhesive 7 is cured for the fastening after the positioning, the positions of the lens 5 and the like tend to be displaced due to volumetric shrinkage of the adhesive 7.